1. Field of the Invention
The present invention relates to an electrical connecting structure between two circuit boards, and more particularly, to an electrical connecting structure suitable for a mounting structure of a tape carrier package (TCP) with a circuit board.
2. Description of the Prior Art
A liquid crystal display (LCD) uses TAB (tape-automated bonding) tape carrier as a means of connecting its printed circuit board to the electrodes on the glass board of its liquid crystal panel. A LCD driver chip is mounted on the TAB tape carrier. FIG. 1 shows a conventional LCD driver tape carrier package 10 using TAB technology. The TAB tape carrier 10 has an insulating film tape 11 formed of a polyimide layer, input leads 12 and output leads 14 laid on its surface. The TAB tape carrier 10 has a chip mounting opening 16, which provides a chip mounting site. The input leads 12 extending from the chip mounting opening 16 toward one edge of the TAB tape carrier 10. The output leads 14 extend from the chip mounting opening 16 toward the other edge of the TAB tape carrier 10. A LCD driver chip 18 is connected to the input leads 12 and output leads 14 in the position of the chip mounting opening 16. In this manner, a LCD driver tape carrier package is formed.
After the LCD driver chip 18 is mounted on the insulating film tape 11, a test may be carried out to inspect whether the mounting condition (interconnecting condition) is satisfactory. Traditionally, the LCD driver tape carrier package 10 is placed on a probe card mounted on a probe station. Probe pins are brought into contact with the input leads 12/or output leads 14 of the LCD driver tape carrier package 10, to inspect whether the LCD driver chip 18 is satisfactorily connected to the input leads 12/or output leads 14. For this conventional test method, the alignments of the probe pins with the input leads 12/or output leads 14 are manually operated, which is inconvenient and time-consuming. When the test method is repetitiously performed, the input leads 12/or output leads 14 are easily damaged by the probe pins. Moreover, it is necessary to use the probe station and probe card for this conventional test method. The probe card is expensive with a cost about NT$20,000 per card, and needs to be maintained periodically. Therefore, this conventional test method is uneconomical and inconvenient.
Accordingly, it is desirable to develop an implement, which facilitates the failure analysis for the LCD driver tape carrier package without the above drawbacks.
It is one objective of the present invention to provide an electrically connecting structure of a tape carrier package for a LCD driver, which utilizes an interface disposed between the tape carrier package and a circuit board for improving electrical contact thereof.
It is another objective of the present invention to provide an electrical connecting structure of a tape carrier package for a LCD driver, which facilitates failure analysis thereof.
It is a further objective of the present invention to provide a mounting structure for a LCD driver tape carrier package with a print circuit board, which can repetitiously perform failure analysis without damaging the LCD driver tape carrier package.
It is still further objective of the present invention to provide a mounting structure for a LCD driver tape carrier package with a print circuit board, which is easily assembled with low cost and provides mechanical stability.
In order to achieve the above objectives of this invention, the present invention provides an electrical connecting structure of a tape carrier package for a LCD (liquid crystal display) driver and mounting structure of a tape carrier package with a circuit board using the same. The present electrical connecting structure comprises a circuit board having a plurality of conductive terminals, a conductive member having a plurality of rows of conductive portions formed thereon and a tape carrier package of a LCD driver having a plurality of input leads and a plurality of output leads. The conductive member is disposed between the circuit board and the tape carrier package. The pitch of the conductive portions is smaller than that of the conductive terminals, the input leads and the output leads such that the conductive portions can electrically connect the conductive terminals to the output leads. The present mounting structure of a tape carrier package with a circuit board comprises a circuit board, a holding plate, a conductive member, a tape carrier package for a LCD driver and a base plate. The circuit board includes a plurality of conductive terminals formed on a surface and a first opening formed along one side of the circuit board and adjacent to the conductive terminals. The holding plate is disposed under the surface of the circuit board having the conductive terminals formed thereon. The holding plate has a second opening matched with the first opening and a slot formed in a position thereof corresponding to the conductive terminals. The conductive member is disposed in the slot of the holding plate. The conductive member has a plurality of conductive portions formed thereon for electrically connecting with the respective conductive terminals. The pitch of the conductive portions is smaller than that of the conductive terminals. The tape carrier package for a LCD driver is disposed under the holding plate. The tape carrier package includes a tape carrier and an LCD driver chip. The tape carrier comprises a chip mounting site for mounting the LCD driver chip, a plurality of input leads formed along one side of the taper carrier far from the chip mounting site, and a plurality of output leads formed along the other side thereof near the chip mounting site and corresponding with the slot of the holding plate. The pitch of the output leads is larger than that of the conductive portions of the conductive member so that each output lead is able to electrically connect with one conductive terminal of the circuit board through the conductive portions. The base plate is used for supporting the tape carrier package. The base plate has a recess portion for placing the tape carrier package therein. Since the output leads of the tape carrier package for the LCD driver can electrically connect with conductive terminals of the circuit board through the conductive portions of the conductive member, the output leads can electrically couple to external terminals via the circuit board. As a result, the present mounting structure of a LCD driver tape carrier package with a circuit board can advantageously and repetitiously perform failure analysis via the circuit board without damaging the output leads of the LCD driver tape carrier package.